Connector ring groove centering device



' June 19, 1945. F. R.'HARRIS CONNECTOR RING GROOVE CENTERING DEVICEFiled April 2, 1943 INVENTOR FPFDER/C R. HARRIS A TTORNE Y Patented June19, 1945 I oomqae'roi mo GROOVE CENTERING 1 "'nnvrcnc j I I: Frederic.R; Harris, New.York,.N.TY.. v

1 Application admit- 2'; 1943; se1=iai No.- 48156553 5-GIa ims. ("01.1445219) This invention relates to timberconnections and devicesformfaltifrg and 'ce n-tering grooves for'rec'eiving'shearringsto'prevent relative'ifiove ment-lietween two layers 'of tim'b'eFwhi arecontact-witkr'eacwotherr In modern .timberfconstru'ctibn practicatouseslieai ringsfor h v I v I b'er surface againstslidirrgorworking uponam other. Special tools are used for cutting"grooves'* in the" timbers,a-"spl'rt shear ring is placed in matching grooves in each, and thetimbers are clamped tightly together over the shear ring by means of astout bolt. I v

It is an object of this invention to provide means for enabling ashearring groove to be cut arounda bolt hole, the axis of which is notperpendicular to the timber surface in which the groove is to be cut,and impart to the groove the same depth at every point. v

The invention provides a simple and economical tool-holding device orimplement which permits the use of shear rings at locations where it hasformerly been difficult or impractical to lace such rings. This makespossible stronger timber structures and more latitude in the design oftimber trusses.

Another object is to provide a timber connection with a fastening boltand a shear ring between timbers that contact in a plane at an inclinetothe axis of the bolt.

Other objects, features and advantages of the invention will appear orbe pointed out as the description proceeds.

In the drawing, in which like reference characters denote correspondingparts in all the views,

Figure 1 is a sectional view through atimber connection with a-shearring located between two timbers that are clamped together by a boltfastening, the axis of which extends at an angle, other than a rightangle, to the plane of the timber surfaces in which the shear ring isinserted;

Figures 2 and 3 are'sectional views illustrating a tool-holding deviceembodying this invention,

and showing a groove cutter in position for making the shear ringgroovesfor the timber connection of Figure 1.

Figure 4 is asectional view taken on the line 44 of Figure 3.

Figure 1 shows two timbers l and H clamped together by a bolt l2. 1 Thisbolt has the conventional washers l3 and I4 against the two outsidesurfaces of the timbers. The nut l5 clamps against the washer I4, andthe adjacent timber merrlb'ers m is cut away to provide {a face or seat.for the: Washer normal to the aX-fsWi-tlfebolt 'l 22 The ti-mliers Wandl lmaya be .portionsiaof-x a truss; or some-= other unit" which mustwithstand" considerable stress; Resistanceto slidingrmovea mentor thetir nber l ll or'r the othentimb'er 'l lcarr: be'--*ver-y -much ih creasedby-looatingaashear rings i T rr such' a p'ositibn* that itextends par-tway eac'lrof' the opposirig or inner faces-of the:

l fl and fl I It is-*-evident from Figure 1; however, that these facesof the timbers l0 and l l are not normal to the bore I8 through whichthe clamping bolt l2 extends. Because of this fact, grooves with auniform depth could not be cut in the timbers I0 and H by conventionalgroove cutting tools having holding devices that are centered by thebore which is provided for the fastening bolt.

This invention comprises a tool-holding or centering device 20 having aprojection or stem 2| that fits into the clamping bolt bore [8. Thereisan abutment member, preferably a flange 22, at one end of the shank orstem 2|, and this flange 22 must rest against the surface of the timberin which a groove is to be'cut. The stem 2| makes the same angle withthe contiguous surface of the flange or collar 22 that the axis of thebore I8 makes with the surface of the timber Ill in which the groove isto be cut.

On the other side of the flange 22 there is a projection comprising abearing element 23 having a recess or socket 24, the axis of Which isnormal to the one annular surface of the flange 22 adjacent the stem andwhich is to engage the timber l0.

The axis of the socket 24, therefore, intersects I the axis of the boreH3 at the plane of the timber surface and the socket 24 serves asacentering recess for a groove cutting tool 25. The cupshaped tool 25 hasa center stud 26 that fits into the socket 24a Cutters 2! around theperiphery of the tool 25 out a groove 28 in the timber surface as thetool is rotated.

The flange 22 is preferably circular, but not necessarily so. be usedwith bolt holes of larger diameter by merely placing tight-fittingtubular ferrules or cylindrical shims around the stem 2|. It isadvantageous to make the diameter of the stem 2| equal to that of thesmallest bolt hole with which the device is likely to be used.

Figures 2 and 3 show the centering device 20 keeping the tool in midposition to cut the shear ring groove inthe inner faces of timbers I0and l I respectively. The invention makes it possible The same centeringdevice can to use conventional groove-cutting tools to cut shear ringgrooves of a uniform depth around e clamping bolt holes that are notnormal to he surfaces in which the grooves are to be out. {To be mosteffective it is important that the grooves for receiving the shear ringsbe of uniform depth around their entire circumference.

The timbers are first fitted together and a continuous hole is boredthrough the different timbers. The timbers are then separated and thegrooves are cut, whereupon connectors or shearrings are inserted; thetimbers then are reassembled and the bolts driven or secured home.

The preferred embodiment of the invention has been described, butchanges and modifications can be made, such as adjustable angularity forthe stem 2|, without departing from the invention as defined in theclaims. Obviously, an equivalent design would be to recess the tool studor journal 26, and make the guide 23 solid.

I claim as my invention:

1. A holding implement for a shear ring groove cutter, including a stemto fit a bore inmaterial into which a fastening bolt is to be inserted,a flange on the stem with a flat, lateral surface lying in a plane thatis inclined to the stem and surrounding the latter, said surface beingsituated on the stem side of said implement and adapted to afford asteadying engagement of said implement with said material, and a bearingelement for a cutter tool extending from the flange in a directionsubstantially normal to the plane of said surface.

2. The implement according to claim 1, in which the bearing element hasa central recess in its outer end.

3. An implement to facilitate cutting annular grooves in timber andaround a center that lies in a bolt hole through'the timber at an acuteangle to the surface that is to be out, said implement including aflange, a stem inclined to the plane of the flange on one side thereofto fit the bolt hole, and a bearing stud on the other side of the flangeand substantially normal thereto for a rotating groove cutter, saidbearing having an axis that is normal to said surface when the stem isinserted in the bolt hole and the flange is in contact with saidsurface.

4. A groove cutter holding implement having a stem at one end, aprojection at the other, the axis of the stem and the projection beingout of alinement, and a collar at the junction of the stem andprojection having its lateral surface on the side adjacent the stemsubstantially normal to the axis of said projection.

5. The implement according to claim 4 in which the projection has abearing socket in its outer end.

F'REDERIC' R. HARRIS.

